Portable high-low lp gas torch

ABSTRACT

A HIGH-LOW PRESSURE LP GAS TORCH THAT INCLUDES A PILOT OR LOW FLAME BURNER NOZZLE AND A PAIR OF MAIN BURNER NOZZLES POSITIONED TO BE IGNITED BY THE PILOT BURNER NOZZLE AND PROVIDE A HIGH TEMPERATURE FLAT FLAME, THE MAIN BURNER NOZZLES ARE IN ADVANCE OF THE PILOT BURNER NOZZLE TO PERMIT MAXIMUM UTILIZATION OF THE SURROUNDING ATMOSPHERIC AIR, FLOW OF LP GAS TO THE PILOT BURNER NOZZLE IS CONTROLLED BY A SCREW ACTUATED PILOT VALVE AND FLOW OF LP GAS TO THE MAIN BURNER NOZZLES IS CONTROLLED BY A SQUEEZE ACTUATED VALVE, THE DISCHARGE FROM THE MAIN BURNER NOZZLES IS DIRECTED DOWNWARDLY TO PRODUCE A REACTION FORCE THAT COUNTERACTS SOME OF THE WEIGHT OF THE TORCH.

QJan. .1Z 1971 .B. BRUNNER PORTABLE HIGH-LOW LP GAS TORCH Filed Dec. 3. 1968 mwavrae, 55v B/ZUA/A/Ee ya wlfp aw/sw United States Patent US. Cl. 431-280 Claims ABSTRACT OF THE DISCLOSURE A high-low pressure LP gas torch that includes a pilot or low flame burner nozzle and a pair of main burner nozzles positioned to be ignited by the pilot burner nozzle and provide a high temperature flat flame; the main burner nozzles are in advance of the pilot burner nozzle to permit maximum utilization of the surrounding atmospheric air; flow of LP gas to the pilot burner nozzle is controlled by a screw actuated pilot valve and flow of LP gas to the main burner nozzles is controlled by a squeeze actuated valve; the discharge from the main burner nozzles is directed downwardly to produce a reaction force that counteracts some of the weight of the torch.

BACKGROUND OF THE INVENTION The present invention relates to portable torches and more particularly to a hand-operated high-low flame LP gas torch that is capable of producing flames of such different characteristics that all of such flames cannot now be produced with any single known torch by the adjustment thereof.

Generally these torches are required for such operations as heating, melting, thawing, preheating, drying, disinfecting and weed control. However, since each of these specific uses generally requires a different type of flame, a torchdesigned for each specific purpose must usually be provided.

Obviously, the costs involved in providing a plurality of torches, each having a distinct flame characteristic, is far more costly than the provision of a single torch which is designed so that by a simple adjustment thereof many of the required different types of flame produced by a plurality of torches can be produced by a single torch.

Another factor to be considered is the increased cost involved in the additional storage and transportation of a plurality of torches. Moreover, where a workman, in order to reduce the number of torches he carries for a days service calls selects, in advance, only those torches he believes will be necessary, finds that he has failed to include a particular torch, much valuable time is lost in returning to the torch storage facility to obtain the proper torch. Again, because of the size of present day commercial torches that are necessary to perform certain operations and the weight of the material used in constructing them, a plurality of such torches are usually difficult to transport and each is difficult to manipulate.

Taking into consideration the foregoing deficiencies, it is the primary object of the present invention to provide a portable hand-operated high-low LP gas torch that eliminates all the above-mentioned deficiencies and is reliable in operation.

Another object of the present invention is to provide a device that can function satisfactorily where portable direct fire or heat is needed for any such operations as heating, melting, thawing, preheating, disinfecting and weed control.

Still another object of the invention is to provide a torch that is constructed, as much as possible, of aluminum parts, so that it will be relatively light in weight when compared to similar known torches and, therefore, easy to transport and manipulate.

Yet another object of the present invention is to pro- 3,554,679 Patented Jan. 12, 1971 vide an individually controlled adjustable pilot or small burner that is capable of producing a flame that may be varied from a very soft six-to-ten inch long flame up to a roaring two foot long high velocity flame.

A further object of the invention is to utilize the small burner flame as a pilot flame for the main burner that includes a quick opening valve which, when operated to open position, provides a large volume of flow of LP gas when a large flame or large amounts of heat are required.

A further object of the invention is to produce a flame pattern utilizing the maximum amount of unrestricted atmospheric air to produce a combustion mixture of 2000 degrees temperature and a high velocity, broad type flame.

A still further object of the invention is to provide a torch which handles especially easy and without material fatigue to the user due to the fact that the flame discharged by the main burner is directed downwardly by an angled nozzle arrangement which actually causes a recoil lift of the entire burner assembly.

A still further object of the present invention is to provide a flattened truncated conical cone shaped cover for the pilot burner that includes a burner chamber which is of sufficient length to prevent wind from extinguishing the pilot or small burner flame.

The invention will be better understood and objects other than those set forth above will become apparent after reading the following description thereof. Such description refers to the annexed drawings presenting preferred and illustrative embodiments of the invention.

In the drawings:

FIG. 1 is a side view of a hand-operated high-low LP gas torch according to the present invention.

FIG. 2 is a longitudinal section through the gas torch illustrated in FIG. 1.

FIG. 3 is a sectional wiew of the torch taken along section line 3-3 of FIG. 1.

FIG. 4 is an end view of the torch when viewed from the direction indicated by the arrows 44 in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, it is to be noted that the torch T disclosed therein includes a combination pilot bypass and quick lever operated valve having a valve body 10 provided with an inlet passage 12 that is screwthreaded at 114 to receive the screw-threaded end 16 of an inlet nipple 18. The valve body 10 is provided with a LP inlet gas chamber 20 that is supplied through the inlet nipple 18.

Valve body 10 is open at its upper end and this upper end is screw-threaded at 24 to receive a screw-threaded valve body closure plug 26. Valve body 10 is provided with a LP gas main burner outlet chamber 28, that is in communication with an annular space 30, formed between the valve body closure plug 26 and the valve body 10, by means of the valve body passage 32. Communication is established between LP gas chamber 20 and the annular space 30 by enlarged passage 34 formed in closure plug 26 and radial passages 36. Flow of LP gas from the inlet gas chamber 20 into enlarged passage 34, radial passages 36, annular passage 30 and valve body passage 32 into burner outlet chamber 28 is controlled by a main valve head 38. Main valve head 38 is biased to its seat 40 by a spring 42 that is engaged, at one of its ends 44, with the bottom wall of a recess 46. At its other end, the spring 42 engages the bottom of the valve head 38 and surrounds a cylindrical projection 48 that extends from the bottom of the main valve head 38.

Valve body 10 is also provided with a LP gas low or pilot burner outlet chamber 50 that is in communication with LP gas inlet chamber 20 and recess 46 by means of passage 52, pilot valve chamber 54 of pilot valve 56 that is formed integral with valve body and passage 58. Flow of LP gas to the low or pilot outlet chamber is controlled by a pilot valve member 60 provided with a valve stem 62 which terminates in a pilot valve head 64 that cooperates with a pilot valve seat 66. The valve stem 62 is provided with screw threads 68 that cooperate with screw-threads 70 formed in the valve body 10 to move the pilot valve head 64 to and from its associated pilot valve seat 66, depending on the direction in which the valve stem 62 is turned by the knurled head 72 at the end of the valve stem 62.

Attached to the side of the main valve head 38, opposite cylindrical projection 48, is a main valve head 38 operating stem 74 that extends through enlarged passage 34 and an opening 76 provided in closure plug 26 to the exterior of the closure plug 26. An annular groove 80 is formed in the periphery of valve head operating stem 74 and into this annular groove 80 there is inserted an O- ring or similar sealing element 80 that forms a seal between the periphery of valve head operating stem 74 and the wall of opening 76.

Mounted on and extending for substantially the entire length of nipple 18 is a handle 82 formed of any suitable insulating material such as wood or plastic. A squeeze lever 84, that is pivoted at 86 to a lever support arm 88, extends in closely spaced relation to and longitudinally along handle 82.

The end of the wall that forms the LP gas outlet chamber 28 of the valve V is threaded at 90 on its interior and at 92 on its exterior. A first portion 94 of a main burner conduit is threaded at its inner end into a fitting 96 which in turn is threaded into the threads 90 formed on the interior of valve body 10. A pilot burner conduit 98 extends through the first portion 94 of the main burner conduit and is secured at its inner end to the low or outlet burner outlet chamber 50 of valve body 10 by a compression type fitting 100. A coupling 102 is threadedly mounted on the outer end of the first portion 94 of the main burner conduit and supports one end of a cover tube 104. The other end of the cover tube 104 is threadedly secured to the screw threads 92 formed on valve body 10.

A second portion 106 of the main burner conduit is threaded into the other end of coupling 102 and has an inner end portion 108 that is axially aligned with the first conduit portion 94 of the main burner conduit and an outer end portion 110 that extends at an angle to said first conduit portion 94.

The pilot burner conduit 98 also extends through the coupling 102 and through and beyond the outer end of the second portion 106 of the main burner conduit. The outer end 110 of the second portion 106 of the main burner conduit is screw-threaded at 108a and has threadedly mounted thereon a burner assembly 112. The burner assembly 112 comprises a flattened truncated cone shaped hood 114, the rearward end of which is closed and the forward end of which is open, as shown, and in the interior of which is located an LP gas distributing block 116. Distributing block 116 has a distributing chamber 118 in fluid communication with the interior of the outer end 110 of the second portion 106 of the main burner conduit.

A pair of diverging passages 120', 122 extend from the LP gas distributing chamber 118 and terminate in threaded outlets 124, 126 adjacent the interior surface of the cone shaped flattened hood 114. Main burner pipes 130, 132 are, respectively, threaded into the outlets 124, 126 and are of such a length that main burner nozzles 134, 136 attached and in communication therewith extend beyond the end of the hood 114 and lie in the same plane as will become apparent on reference to FIG. 4 of the drawings.

A pilot burner nozzle 138 is screwed into the LP gas distributing block 116 and is placed in communication with the pilot burner conduit 98 by means of a compression type fitting 140. The outlet of the burner noule 138 is arranged to lie in the same central longitudinal plane as the outlets of the main burner nozzles 134.

In order to make full use of the portable hand-operated high-low flame LP gas torch that constitutes the present invention, it is essential to determine first what type of flame is required for carrying out a particular operation and to then adjust the torch so that the flame it delivers will be suitable for that operation. For example, with the main burner valve head 38 held to its seat 40 by the spring 42, flow through the main burner conduit to the main burner nozzles 134, 136 is precluded. By turning the knurled head 72 at one end of valve stem 62, in one direction or the other, the amount of LP gas that may flow from the LP gas inlet chamber 20, through passage 58, chamber 50, pilot burner conduit 98 and pilot burner nozzle 138 may be controlled to provide a pilot flame that can be varied from a very soft 6 to 10 inch long flame up to a roaring two foot long, high velocity flame. Such a flame is ideal for many outdoor on-the-job heating applications such as heating or melting asphalt in the roofing trade, disinfecting poultry egg cages or for use in close areas where large amounts of heat cannot be tolerated.

When large amounts of heat are required, the knurled head 72 is adjusted to provide for the delivery of a pilot flame from pilot burner nozzle 138. Squeeze lever 84 is then actuated to unseat valve head 38. LP gas then flows through enlarged passage 34, radial passages 36, annular space 30, valve body passage 32, main burner outlet chamber 28, main burner conduit portion 94, coupling 102, main burner conduit portion 106, distributing chamber 118, diverging passages 120, 122, and burner pipes 130, 132 to main burner nozzles 134, 136. The LP gas delivered by the main burner nozzles 134, 136 is ignited by the flame from the pilot burner nozzle 138 and produces a flame pattern utilizing the maximum amount of unrestricted atmospheric air to produce a combustion mixture of 2000 temperature and a high velocity, broad type flame of four feet in length and ten inches wide at 5 to 30 p.s.i., and fourteen inches wide at to 200 p.s.i. This type of flame has been found to be ideal for drying chuckholes before new patching mix is applied, for thawing frozen manhole covers and large water pipes, for preheating large sections of pipe before field welding, for controlling green weed growths along fence rows, drainage and irrigation ditches, roadways, storage areas and areas where toxic chemicals would be dangerous to use.

Due to the location of the main burner nozzles 134, 136 in front of the pilot burner nozzle 138, there is a maximum utilization of the surrounding atmospheric air without restrictions of any type. Accordingly, because of the specific positioning of the main burner nozzles a high temperature, high velocity, flat flame will be produced by the torch T.

Although the weight of the torch T will be reduced when compared with other torches because many of its parts are made of light weight material, its effective weight will be further reduced because the outer end portion 110 of the main burner conduit extends at a downward angle to the first conduit portion 94 when the torch is in its normal, substantially horizontal operating position shown. This results in an LP gas discharge from the main burner nozzles that is directed downwardly and creates an upward reaction force in opposition to the force of gravity.

Finally, it should be noted that the burners of the torch T operate equally as well at a tank pressure that may vary between 0 and 300 pounds or with a pressure regulating device to maintain specific flame length or temperatures.

After reading the foregoing detailed description, it will be apparent that the objects of the invention set forth initially have been successfully achieved. Accordingly, what is claimed is:

1. A hand-operated high-low LP gas torch comprising a valve body means having an inlet passage means; a

pair of outlet passage means each in communication with the inlet passage means; an independently operable valve ineans in each of the outlet passage means for controlling the fiow of LP gas through said outlet passage means; pilot burner conduit means connected to and in communication bfyith one of said outlet passage means; a main burner conduit means connected to and in communication with the "other of said outlet passage means; and a burner assembly means including a burner hood means having a closed {iiearward end and an open forward end, a pilot burner nozzle means adjacent said closed rearward end, a pair of main burner nozzle means each of which is located adjacent said open for-ward end, forwardly and laterally of 's faid pilot burner nozzle means; and means" establishing communication between said pilot burner nozzle means and said pilot burner conduit means and between-said main burner nozzle means and said main burner conduit means.

f, 2. A hand-operated high-low LP gas torch as defined in claim 1 wherein the pilot burner nozzle means and the main burner nozzle means lie in the same central longitudinal plane.

3. A hand-operated high-low LP gas torch as defined in claim 1, wherein an end portion of the main burner conduit means remote from the valve means is disposed at a downward angle when the torch is disposed in a substantially horizontal operating position, whereby the reaction force of the LP gas discharged from said main burner nozzle means tends to counterbalance the weight of the torch.

4. A hand-operated high-low LP gas torch as defined in claim 1 wherein the valve body means end of the pilot burner conduit means is secured to the valve body means by a compression type fitting means.

.5. A hand-operated high-low LP gas torch as defined in claim 1 wherein the burner assembly means end of the pilot burner conduit means is secured to the burner assembly means by a compression fitting means.

L6. A hand-operated high-low LP gas torch as defined in claim 1 wherein the burner hood means of the burner assembly means is of flattened truncated cone shape.

{7. A hand-operated high-low LP gas torch as defined in claim 1 wherein a cover tube is mounted on said valve body means and said main burner conduit means arranged in spaced relationship to said main burner conduit means.

8. A hand-operated high-low LP gas torch as defined in claim 1 wherein an inlet nipple means is secured to said inlet passage means and has mounted thereon a handle of low heat conductivity.

9. A hand-operated high-low LP gas torch as defined in claim 1 wherein the valve means that controls flow of LP gas to said main burner nozzle means is spring biased to closed position and is actuated to its open position by a pivotally mounted lever.

10. A hand-operated high-low LP gas torch as defined in claim 1, wherein said main burner nozzle means and said pilot burner nozzle means lie in the same central longitudinal plane; an end portion of the main burner conduit means, remote from the valve means, is directed at a downward angle when the torch is disposed in a substantially horizontal operating position and tends by the reaction force of the gas discharged from the main burner nozzle means to counter-balance the weight of the torch; the pilot burner conduit means is secured to the burner assembly means and to the valve body means by compression type fitting means; the burner hood means of the burner assembly means is of flattened truncated cone shape; a cover tube is mounted on said valve body means and said main burner conduit means in spaced relation to said main burner conduit means; an inlet nipple means is secured to said inlet passage means and has mounted thereon a handle of low heat conductivity; and said valve means that controls the flow of LP to said main burner means is spring biased to closed position and actuated to its open position by a pivotally mounted lever that extends in spaced relation along said handle.

References Cited UNITED STATES PATENTS 2,013,683 9/1935 Coleman 431-278 2,880,793 4/1959 Golden 431-278X 3,198,239 8/1965 Webster 431278 EDWARD L. FAVORS, Primary Examiner US. Cl. X.R. 

